B320i controller: Side effects of enabling physical drive write cache state

I have an HP ProLiant DL360e (G8) with B320i controller. I want to enable physical drive write cache state.   It seems easy to do this from the HP Smart Storage Administrator | Modify Controller Settings.  My two questions are about the side effects.
1)  Does this force a rebuild of the drive array?  Cannot live with this!
2)  Does it require a reboot?